Question

An astronaut with a mass of `110 kg` is floating in space. If the astronaut throws a `70 kg` object at a speed of `4 m/s`, how much will his speed change by?

Answer 1

Sum impulses stays constant, or `summ*v=C`

Explanation:

Change (`Delta`) in impulse in one direction (object):
`m_o*Deltav_o=70*4=280kg*m//s`

`Delta` Impulse in the opposite direction (astronaut):
`m_a*Deltav_a=110*Deltav_a=280->Deltav_a=280/110=2.545m//s`